Is Sapphire Glass Going to Replace Gorilla Glass?

What do military armor, your grandmother’s jewelry box, and your next smartphone screen have in common?

The answer — which may surprise you — is sapphire.

The second hardest natural substance after diamond, sapphire has caught the attention of technology manufacturers, who are exploring the possibility of using it for smartphone and tablet screens.

In addition to being a popular gem, sapphire is used to make bullet-proof glass, watches, and the front windows of barcode scanners. The military currently uses sheets of sapphire glass to make transparent armor. Sapphire glass is also used in aeronautics.

The substance is hard-wearing, shock-resistant, and about 10 times more scratch-resistant than normal window glass, making it a great option for personal devices that are susceptible to daily wear-and-tear. Sapphire is also very rigid and won’t buckle or melt when subjected to high temperatures.

How Sapphire Glass is Made

Generally, synthetic sapphire is manufactured by melting aluminum oxide in a special furnace, and letting it cool into a single crystal of sapphire. The crystal can then be cut with a diamond saw into sheets or wafers.

Pure aluminum oxide creates a transparent sapphire crystal; to create the colored blue sapphire or even ruby, trace minerals must be added.

The Future of Smartphone Screens?

Technology experts believe that sapphire would better protect smartphone screens and prolong their lifetime. The marketing director of GT Advanced Technologies, Jeff Nestel-Patt, told reporters at the Mobile World Congress in Barcelona earlier this year that sapphire glass is two and a half times stronger than reinforced glass commonly used to make smartphone screens. “It’s virtually scratch-free,” he said.

GT showed MWC attendees a demo of an iPhone, retrofitted with a sapphire glass screen protector, struck repeatedly with a large piece of concrete. The sapphire glass protector actually broke up the concrete, creating a dust that was easily wiped away, and leaving the cell phone without a single scratch.

The sapphire glass-fitted screen was also very responsive to the touch of the user’s fingertip.

Scratch-Free — At a Price

However, this kind of strength is not cheap. Mr. Nestel-Patt believes that sapphire glass, although not yet commercially available through GT Advanced Technologies, is three to four times more expensive than reinforced glass. Another market analyst said that a sheet of Corning’s Gorilla Glass costs about $3, compared to the $30 price tag for a piece of sapphire glass.

Luckily, rising competition and mass production should drive down the price. Analysts believe that in two to three years, most smartphone screens will be made of sapphire glass.

Apple has already invested in the technology, and put sapphire glass on the iPhone 5’s rear camera lens.

Cracked smartphone and tablet screens will soon be merely a memory, thanks to the development of sapphire glass.